Who is Mike Robe?

Pardon our manners! We've yet to formally introduce our officially unofficial mascot, our freelance bacterium compostium, Mike Robe! Some of you may have been wondering, "Who (or what) in the world is Mike Robe?" Well, he's a microbe.

Without microbes, we wouldn't have compost. Let's explore why!

In the process of composting, microorganisms and microbes break down organic matter and produce carbon dioxide, water, heat, and humus (another term for well-aged compost).

Generally, the composting process moves through three phases:

1. The mesophilic, or moderate-temperature phase, which lasts for a couple of days

2. The thermophilic, or high-temperature phase, which can last from a few days to several months

3. A several-month cooling and maturation phase.

Different communities of microbes thrive during the various composting phases.

Initial decomposition is carried out by mesophilic microbes, which rapidly break down the soluble, readily degradable compounds. The heat they produce causes the compost temperature to rapidly rise.

As the temperature rises above about 100°F, the mesophilic microbes become less competitive and are replaced by others that are thermophilic, or heat-loving.

At temperatures of 130°F and above, many microbes that are human or plant pathogens are destroyed. Because temperatures over about 150°F kill many forms of microbes and limit the rate of decomposition, composters use aeration (introducing oxygen to the pile) and mixing to keep the temperature below this point.

During the thermophilic phase, high temperatures accelerate the breakdown of proteins, fats, and other major structural molecules in plants. As the supply of these high-energy compounds get low, the compost temperature gradually decreases and mesophilic microbes once again take over for the final phase of "curing" or maturation of the remaining organic matter. And the end result after all those microbes feast: beautiful, compost.

So thanks Mike Robe, to you and your microbe friends and family, for all that you do. You make composting possible!